The invention relates to an optical fiber fusion splicer and an optical fiber loading device thereof, which provides highly precise alignment positioning of end faces of optical fibers, of optical fiber cables, to each other to be brought in contact for fusion splicing.
Fusion splicing end faces of optical fibers of optical fiber cables to each other requires highly precise alignment positioning. Thus, a fusion splicer requires a V-groove block with a highly precisely machined V-groove. Positioning of the optical fibers of the optical fiber cables by the fusion splicer requires: (1) wear resistance; (2) heat resistance; (3) a small linear expansion coefficient; and (4) electric insulation.
A related fusion splicer is disclosed in Japanese Examined Patent Application No. H07-43453. This fusion splicer includes a standing body frame for fusion splicing. The fusion splicer has, at the left and right portions of the body frame for fusion splicing, for example, leftward and rightward movable left and right fiber holders. The left and right holders have a lower left fiber holder and a lower right holder; and an upper left holder and an upper right holder, respectively. The upper left holder and the upper right holder are vertically movable relative to the lower left fiber holder and the lower right holder using, for example, a hinge pin. The lower left holder and the lower right holder have surfaces that each has, for example, upward open rectangular grooves for holding, for example, an optical fiber ribbon cord with four optical fibers.
The body frame for fusion splice inside the left fiber holder and the right fiber holder has a loading device located thereof. The loading device includes, for example, a resinous loading body frame on the body frame for fusion splice. The loading body frame has a recessed shape as viewed from front, with a recessed portion at the substantially central portion between the left and right and between the front and rear of the body frame. The recessed portion has, at the front and rear, holes communicating with the recessed portion. The loading body frame includes, thereon, a ceramic block identical in shape with a lower clamp, as viewed from top. The ceramic block has a recessed portion; and identically shaped holes positioned in coincidence with the hole. The loading body frame has, thereon, a ceramic block integrally adhered thereto using an adhesive.
Ceramic block portions opposed to each other relative to the recessed portion in a left and right direction have surfaces with V grooves extended in the left and right direction. For clamping optical fibers exposed by removing sheaths from optical fiber ribbon cords, upper clamps are provided to be vertically movable relative to the ceramic blocks.
The related fusion splicer has the following problems: (1) the ceramic block has a large size and expensive production costs; (2) the ceramic block has complicated machining and expensive production costs; and (3) poor adhesion causes the ceramic block to be separated form the body frame, thus putting the fusion splicer out of use.